1. Field of the Invention
The present invention relates to a safety helmet for cranial protection. More particularly it relates to a modular helmet apparatus constructed of interchanging cooperative components of differing sizes which provide a prophylactic helmet to be worn by patients undergoing general anesthesia to prevent eye, skin, or other nerve damage from prolonged pressure upon areas of the head as well as to provide a safer manner for cranial manipulation during surgery.
2. Prior Art
Surgeries upon patients in the prone position present a number of patient care challenges to the anesthesiologist and surgical staff. Once a patient undergoing a surgery requiring general anesthesia is anesthetized, that patient is essentially in a coma like state. In such a state, noxious stimuli to the patient's body and skin, such as pressure or pain, which would normally cause an awake patient to move to relieve the stimulus, no longer causes such a reaction. Consequently, patients under general anesthesia are especially threatened by a number of factors, other than the surgery itself, which arise during such surgical procedures.
One hazard which requires constant vigilance by the surgical staff to protect against injury is the threat of eye damage. Inadvertent pressure upon the ocular structures of a patient for just a matter of minutes can cause extreme damage or blindness to the eye. As noted above, because the anesthetized patient is in a coma like state, the discomfort of facial compression upon the eye, which would normally cause an awake patient to move and relieve that pressure, fails to alert the anesthetized patient. Care must be taken by an ever alert surgical staff to inspect for possible pressure points about the ocular structures of the patient and to move the patient's face to prevent eye damage.
Other compression injuries can occur to the anesthetized patent's forehead and chin areas. Here again, the constant pressure upon those areas, caused by the weight of the patients own head, if not relieved by movement of the face to allow blood flow thereto, can cause localized ischemia to the chin and forehead area. Since the anesthetized patient does not react to the body's cues of discomfort preceding injury, the risk of harm in a matter of minutes to these areas is great.
Currently, there are a number of conventional methods to support the head and protect the eyes and face of a patient from compression injuries during surgery which require the patient to be placed in a prone, face down, position for the long periods of time involved in surgery. One method conventionally used is placement of the patient's head and face in a horseshoe shaped frame supporting a foam pillow which holds the patients face off of the operating table in a supported manner. The patient's eyes are generally taped shut when such a structure is used to keep them from contact with the foam and to prevent eye fluid drainage. This frame and pillow support however has inherent hazards of its own in that it cannot distribute pressure maximally over the surface of the head. Further, great care must be taken by the anesthesiologist and staff to make sure that any anesthetic equipment, such as endotracheal tubes, esophageal stethoscopes, or electronic sensing devices, are not dislodged or disrupted by gravity or patient positioning during the term of the surgical procedure. Such disruption or dislodgement of surgical equipment can cut off the air supply to the patient or lead to inaccurate readings by monitoring equipment.
Another method is simply to place the patient's face sideways on a pillow or towel located upon the surgical table. However, this method suffers from the danger of tubing collapse due to the patient's head weight, and even a face or eye supported by a foam pillow may be damaged if the pressure is uneven and remains on one area too long. Further, the placement of the patient's face on a towel requires the head to be turned one way or the other, placing pressure on one side of the face which, as noted earlier, subjects the patient to the potential of injury. Additionally, blood flow through the veins and arteries of the neck may be impaired by this twisted fashion of head support. Hazards to the patient increase if the surgery requires a face down posture because the danger of tube collapse from pressure or bending increases with the tubes entering the patient's body through the mouth or nose being compressed between the patient's face and the operating table. With the entry points to the head out of view, such constrictions of the tubes also remain out of sight.
A further challenge facing surgical teams during surgery on anesthetized patients is the seemingly simple task of rolling the patient over from a supine position to a prone position on the operating table or from a cart onto the operating table. Generally, the patient at this point in the surgical procedure is already intubated, asleep, and basically "dead weight." In this physical state, the patient is at great risk of injury during the roll over procedure, especially to the neck area. Additionally vexing to the surgical staff is the fact that the patient, with tubes exiting the mouth and/or nose, must be rolled over, without disturbing the tubes and without injuring the neck. Concurrently during the roll over procedure, the surgical staff must plan ahead so that when the patient is placed face down on an operating table, the face is properly aligned with, and inserted upon or into the pillow, already located upon the table. This insertion of the face into the pillow is conventionally done without the benefit of a pre surgery fit to make sure the face and pillow and frame mate in a manner that will accommodate the patient for the term of the surgery and protect the face from compression injury. Heads and faces being quite different amongst people in general, an optimum fit between face and pillow is achieved only a small percentage of the time. Once in this prone position, the danger of injury remains constant and continued and consistent vigilance by the surgical staff is required to ascertain, that in fact, the patient's airways are open, the eyes are not compressed, and the face is not being subjected to pressure at any point for a duration sufficient to cause nerve damage.
Finally, when the operation is over, the patient must again be moved off of the operating table and is generally rolled over onto a gurney in a reverse roll over procedure. Still anesthetized, the patient is at great risk of injury to the neck if the head is not adequately supported and manipulated during this roll over process.
Still further, if an emergency develops while the patient is in the face down prone position, requiring the patient to be rolled to the supine position, valuable life saving time can be lost trying to upright the patient without injury to the neck, and without crimping the airway supply tubing and monitoring equipment communicating through the nose and mouth of the patient.
Further, patient size is also a factor in the fitting of facial and head support. A child may have a very small face and head and an adult a large one. Conversely, a large child may have a head and face requiring support in areas much different from a small stature adult.
U.S. Pat. No. 5,220,699 (Farris) teaches an inflatable pillow mounted inside a mask for variable support of differing sized patients. However Farris requires the use of an inflatable chamber which as taught is inflated once the patient has already been rolled to the prone position. It requires an air inflation device to function and lacks the ability for an easy installation prior to surgery and will not function without compressed air.
U.S. Pat. No. 4,400,820 (O'Dell) teaches an apparatus using pads and having a "T" shaped void which may be used in combination with a support structure to hold the patient's head. However, O'Dell does not allow for pre-fitting and pre-installing the protective device prior to surgery and does not aid in protecting the patient during roll over on and off the table.
U.S. Pat. No. 5,214,815 (Agbodoe) teaches a surgical headrest with a removable foam pad; however, Agbodoe does not provide any manner to pre-fit and install the device on the patient prior to being asleep and it mounts to the table and is intended for use after roll over thereon.
U.S. Pat. No. 4,757,983 (Ray) features a pair of cushions attached to a horseshoe shaped frame for surgical head support. However Ray also suffers from an inability to pre-fit and install the device on patients prior to surgery while they are awake as well as lacking any protective ability during dangerous roll over onto the table.
As such, there exists a need for a support device that is easily modified to fit a variety of patients of differing size, that may be pre-fit and pre-attached to the patient prior to surgery while the patient is alert and able to ascertain the comfort or discomfort level of the device. Further such a device should provide an additional manner to support the head and maximally diffuse pressure over a large area, during surgery, as well as during the hazardous movement of the patient prior to and after surgery.